This invention relates generally to the field of aerostructures and, more specifically, to a system and method for deflecting an aerodynamic control surface.
Control surfaces, such as flaps, ailerons, and elevators, control the direction of, and provide stability for, aeronautic vehicles, such as aircrafts. Control surfaces accomplish this control by being driven by various actuation systems. Manufacturers of control surfaces and their corresponding actuation systems desire simple designs for safety reasons and for saving space inside a wing. In addition, control surface manufacturers design and construct control surfaces to handle high aerodynamic loads and to respond quickly to pilot inputs. Some aerodynamic applications require that control surfaces accomplish large deflections quickly and smoothly to increase aerodynamic efficiency.
Some previous actuation systems, such as hydraulic, pneumatic, electro-mechanical, and electro-hydraulic systems, require many components to construct a single actuator. In addition, some of these previous systems require a high-force actuator with a long stroke. The complexity and operation of these previous systems prevent the usage of multiple actuation systems for added redundancy and improved safety. Additionally, the complexity of these previous systems wastes considerable space that can reduce fuel storage area. Additional problems with these previous systems, among others, is that they have relatively slow response times and are unable to facilitate the use of multiple control surfaces in a smooth, economical, and efficient manner.
The challenges in the field of aerostructures continue to increase with demands for more and better techniques having greater flexibility and adaptability. Therefore, a need has arisen for a new system and method for deflecting an aerodynamic control surface.
In accordance with the present invention, a system and method for deflecting an aerodynamic control surface is provided that addresses disadvantages and problems associated with previously developed systems and methods.
According to one embodiment of the invention, a system for deflecting an aerodynamic control surface includes a first piezoelectric actuator coupled to a first flexure member. The first flexure member has a first end coupled to a first surface of the aerodynamic control surface and is operable to amplify a linear motion of the first piezoelectric actuator. The system further includes a second piezoelectric actuator coupled to a second flexure member. The second flexure member has a first end coupled to a second surface of the aerodynamic control surface and is operable to amplify a linear motion of the second piezoelectric actuator.
According to another embodiment of the invention, a method for deflecting an aerodynamic control surface includes rotatably coupling a first end of a first flexure member to a first surface of the aerodynamic control surface, rotatably coupling a first end of a second flexure member to a second surface of the aerodynamic control surface, rotatably coupling a first piezoelectric actuator to the first flexure member, rotatably coupling a second piezoelectric actuator to the second flexure member, electrically coupling an electronic power source to the first and second piezoelectric actuators, and inputting a first electrical charge into the first piezoelectric actuator and a second electrical charge into the second piezoelectric actuator. The first and second flexure members, in conjunction with one another, translate a first linear motion of the first piezoelectric actuator and a second linear motion of the second piezoelectric actuator into a rotational motion of the aerodynamic control surface.
Embodiments of the invention provide numerous technical advantages. For example, a technical advantage of one embodiment of the present invention is that a small piezoelectric actuator stroke produced at a high rate and force allows useful control surface deflections. Another technical advantage of one embodiment of the present invention is that the simplicity of a piezoelectric actuation system allows multiple control surface usage for enhanced safety and larger control surface deflections. In addition, the use of multiple control surfaces results in smooth control surface deflections that have maximum aerodynamic efficiency.
Other technical advantages are readily apparent to one skilled in the art from the following figures, descriptions, and claims.